hile bill increases at Britain’s largest energy companies have commanded the headlines after the regulator’s decision to raise its price cap, nine smaller suppliers have quietly followed suit.

The cap, introduced in January and applying to variable tariffs, will increase by £117 in April to £1,242 a year for the average user.

The Big Six energy firms were quick to follow suit, but some of the so-called “challenger” suppliers have not been far behind.

Analysis by switching site uSwitch shows that Ebico announced the largest increase to its standard tariff – 16pc – bringing it to £1,227 a year, closely followed by Tonik Energy, which announced a hike of 14pc.

Ovo Energy is applying a 10pc increase to 160,000 households on its “Simpler Energy” tariff.

Rik Smith, of uSwitch, said: “If your supplier has priced within a few pounds of the cap, you’re on a bad deal.”

Two suppliers have announced decreases to bills in the past weeks. Bulb, which now boasts one million customers, has cut bills by an average of £20 a year, and Igloo Energy has sliced tariffs by 2.6pc.

The price cap imposed by industry regulator Ofgem can be increased in line with the underlying cost of energy. This wholesale cost has actually been falling in recent months, but the cap is set by considering the shift in prices dating back around six months.

This means the cap is likely to decrease when the next change is announced in October.